Most power out a Nord Engine Naturally Aspirated

[raff_gta]

Just wondering what is the highest power figure achieved with a Nord four cylinder, totally naturally aspirated?

I know Autodelta were getting 230-240hp with the GT Am, but were their higher power figures? and has anyone anywhere been able to get more than 250 out of one?

cheers guys!

[genericwood]

Raff, of course the GTAm was not really a Nord engine. I doubt anyone has been able to get over 210 hp out of a single-plug 2L. Most of the really serious 2L race engines make around 200 hp. Unfortunately, you just can't get them to breathe well enough to make much more.

Erik

[JoeCab]

Quote:

Originally Posted by genericwood I doubt anyone has been able to get over 210 hp out of a single-plug 2L. Most of the really serious 2L race engines make around 200 hp.

[Alfar7]

1990 cc breathing through small valve 1750 head. 217 HP. But better yet, above the 2 century mark for 1400 RPM Owner a BB member. He can post dyno results if he desires.

Rj

[raff_gta]

woah! 14000 rpm! thats ridiculous! Im interested in even the twin plug motors, but from what Ive been told, they dont make too much more power anyway do they?

p.s the power that the car is making in that graph, thats at the wheels right?

[raff_gta]

And another thing, what makes the Nord Motor fail at revs? Bent rods? Thrown rods? Seized/spun bearings?

[bianchi1]

208 hp ..but only 135 torque?

[Subtle]

?????--Indeed????

[PSk]

Quote:

Originally Posted by raff_gta woah! 14000 rpm! thats ridiculous! Im interested in even the twin plug motors, but from what Ive been told, they dont make too much more power anyway do they? p.s the power that the car is making in that graph, thats at the wheels right?

[raff_gta]

i dont want to build one, I just want to know whats the best people have got out of them. Yes you could get a Honda, but they are pieces of crap anyway so whats the point.

[alfaparticle]

I think that Richard's post means that the over 200 hp power band is 1400 rpm wide.

[Alfar7]

First, since I posted this above the equator you will need to turn your monitor upside down, or if less trouble due to wiring, stand on your head

Up here 1400 RPMs is just that. I was not aware that an additional 0 was added into the either that you pull the data from.... I`ll work on getting Simon to address that problem.

To clarify it a bit for you, the motor described made maximum HP of 217, and was above 204 HP and 173 lbft tq. from 6200 RPM to 7700 RPM. (sorry, 1500 rpm band not 1400 as first stated) and done by 2 of the most respected builders in our clan... and using a little head. Not their little heads, a 1750 head. But the motor was almost 2 liters, 1990cc!
It`s all about the cams you know

[Subtle]

I read Rj's statment as it was intended--1500 is more than an improvement in arithmetic.

[raff_gta]

obviously the harder it will rev, the more power it will make, but the issue i want to know is why they wont make more power than 220hp? the head doesnt have the best compression chamber ever, but what is stopping these motors from revving? Sure we can spec up a cam to suit 10,000 rpm, but question is, what lets looses before it revs that high?

lol at the aussie reading instructions, my bad, i accidently thought you wrote 14,000 rpm ey

[genericwood]

Raff, our Nord engines are relatively long stroke. The piston speeds can get really ridiculous at 8000+ rpm. Most race engines are running aftermarket rods which can handle it, but both rod and main bearings get very short-lived if you are going to go much higher. Of course, this assumes that you are running lightened valve gear and really good springs.

You are correct about the combustion chamber shape being poor. When you start getting the compression you need to make big power, the shape gets even worse. But the other big limitation is the port angles. It's really tough to get the mixture to turn the corner to fully utilize the valve size.

Erik